import random
number1 = random.randint(0,9)
number2 = random.randint(0,9)

if number1<number2:
    number1,umber2 = number2,number1

answer = eval(input(str(number1)+"-"+str(number2)+"="))

while number1-number2 !=answer:
    answer = eval(input("错误答案，请重新输入\n"+str(number1)+"-"+str(number2)+"="))

print("回答正确")